Displacement amplification self-centering friction damper

A displacement amplification self-centering friction damper, comprising a sleeve, a bushing, a transmission device, a friction device, and a self-centering device;

• the sleeve comprises an outer sleeve and an inner sleeve, wherein the outer sleeve and the inner sleeve form a plug-in nested structure;
• one end of the bushing is fixed to the outer sleeve in ordered to accommodate a first disc-spring, while the other end of the bushing is threaded;
• one end of the outer sleeve and one end of the inner sleeve have a pull ring for connection to external structures respectively;
• a bottom of the inner sleeve is equipped with two racks, which engage with the transmission device;
• the transmission device comprises friction-disc gears, winch gears, a friction-disc, a winch, steel strand, a wire bushing, and a first end cap, where the winch gears, the friction-disc gears, and the winch are inside the outer sleeve, the winch gears are coaxially fixed to the winch, and the friction-disc gears are coaxially fixed to the friction-disc;
• one end of the first end cap is connected to the bushing via threads, while the other end of the first end cap is connected to the wire bushing;
• one end of the steel strand is connected to the winch, while the other end of the steel strand passes through a first hole on the outer sleeve, then through the bushing and entering the first end cap and the wire bushing, and the other end of the steel strand passing through the wire bushing is connected to the friction device;
• the friction device is fixed to an outside of the outer sleeve and next to an edge of the friction-disc, the friction device comprises clamp arms, friction-pads, connecting rods, and second disc-springs, and the friction-pads and the second disc-springs are both fixed on the clamp arms, the clamp arms are connected to the connecting rods;
• the self-centering device comprises a first disc-spring, a first disc, and a first anchor, where the steel strand passes through a center of the first disc-spring and the first disc, and after applying a certain pressure to the first disc against the first disc-spring, the first disc is fixed on the steel strand via the first anchor;
• when the inner sleeve and outer sleeve are subjected to a relative motion in any directions, the transmission device causes the friction-disc to rotate under the drive of the racks, and a relative displacement between the steel strand and the wire bushing drives the friction device to press the friction pads against an edge of the friction-disc, then frictional energy dissipation can be achieved, and a transmission ratio between the friction-disc and the friction-disc gears ensures that a relative displacement between the friction pads and the friction-disc is greater than a relative displacement between the inner sleeve and outer sleeve, thus the displacement can be amplified;
• after the external force is removed, due to the first disc-spring of the self-centering device, the entire device can automatically return to an initial state, providing self-centering capability.